It was a speech so moving the crowd wept. It was a speech so personally important George Washington’s hand shook as he read it until he had to hold the paper still with both hands. After the ceremony, he handed the thing to a friend and sped out the door of the State House in Annapolis, riding off by horse.

For centuries, his words have resonated in American democracy even as the speech itself — the small piece of paper that shook in his hands that day — was quietly put away, out of the public eye and largely forgotten.

Today, however, amid festivities celebrating his birthday, Maryland officials plan to unveil the original document — worth $1.5 million — after acquiring it in a private sale from a family in Maryland who had kept it all these years. It took two years to negotiate the deal and raise money for the speech, which experts consider the most significant Washington document to change hands in the past 50 years.

The speech, scholars say, was a turning point in U.S. history. As the Revolutionary War was winding down, some wanted to make Washington king. Some whispered conspiracy, trying to seduce him with the trappings of power. But Washington renounced them all.

By resigning his commission as commander in chief to the Continental Congress — then housed at the Annapolis capitol — Washington laid the cornerstone for an American principle that persists today: Civilians, not generals, are ultimately in charge of military power.